Vanguard's Last Stand

You point towards a creature you can see as it reaches 0 hit points and incant the power word. The creature instead has 1 hit point until the end of its next turn.

When the creature completes their next turn, if no hit points have been recovered, they fall unconscious with 0 hit points and make a death save that turn as normal.

If this spell is cast after a creature takes damage that reduces their hit points to 0 and the creature takes damage again before their turn, this spell is negated and the creature falls unconscious as normal unless another source casts this spell again.